An ambiguous use of the phrase "take off" was a key cause of the Tenerife Airport Disaster. >As a consequence of the accident, sweeping changes were made to in

An ambiguous use of the phrase "take off" was a key cause of the Tenerife Airport Disaster. >As a consequence of the accident, sweeping changes were made to international airline regulations and to aircraft. Aviation authorities around the world introduced requirements for standard phrases and a greater emphasis on English as a common working language.[13] >Air traffic instruction should not be acknowledged solely with a colloquial phrase such as "OK" or even "Roger" (which simply means the last transmission was received[58]), but with a readback of the key parts of the instruction, to show mutual understanding. The phrase "take off" is now spoken only when the actual takeoff clearance is given or when cancelling that same clearance (i.e. "cleared for take-off" or "cancel take-off clearance"). Up until that point, aircrew and controllers should use the phrase "departure" in its place, e.g. "ready for departure". Additionally, an ATC clearance given to an aircraft already lined-up on the runway must be prefixed with the instruction "hold position".[59] https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster https://web.archive.org/web/20170218144312/http://lessonslearned.faa.gov/ll_main.cfm?TabID=3&LLID=52&LLTypeID=2 https://web.archive.org/web/20170218144312/http://lessonslea...